johnson 140hp not warming up

[boating maniac]

Alright so I have a 1991 johnson 140hp that doesn't run at the proper temp. Apparantly it supposed to run at 120 at full throttle and 150 at idle.

I measured the cylinder head temp with an infrared thermometer and both heads were running at about 85 degrees or so after running the boat. It take about 10 minutes for the engine to settle down and come out of quick start mode. Then after that it runs nice and smooth but still only running at 85 degrees or so.

Here is what I've done so far: New thermostats and gaskets and a new water pump impeller. Still doing the same thing. Someone mentioned something about a water control valve or something that might need to be adjusted. Not really sure what or where that is but what else could cause the engine to not warm up besides bad thermostats and impeller?

Here is the model number: VJ140TLEID

 

[boobie]

Re: johnson 140hp not warming up

The water control valve keeps pressure on the thermos when idleing and as you advance the throttle it releases the pressure. Yes, you could have a problem with it. It's on the starboard side of the mtr. Follow the hoses from the thermos.

 

[boating maniac]

Re: johnson 140hp not warming up

Is this it? Number 37. Is this something that I can just install and nothing needs to be adjusted or anything?

Ok it wouldn't let me post the link to the diagram. But here is the part number is this the control valve your talking about? It connects to the hoses so Im assuming that's it.

0394407 CONTROL VALVE

 

[boobie]

Re: johnson 140hp not warming up

That's the valve, BUT before you replace it make sure all the water lines going to it and from it have no restrictions in them. You can buy parts for the valve on shop.evinrude.com.

 

[Haffiman]

Re: johnson 140hp not warming up

Buy/borrow a water pressure tester. Make a T-connection where the hoses goes into the cover of the thermostats. Pressure here at idle must be the same as the pressure measured at the tell-tale outlet from the exhaust cover.